U.S. Statutory Invention Disclosure H121 discloses various embodiments for a quick release valve for a sprinkler head. Each embodiment includes a sprinkler body defining a flow passage for conducting a fire retarding fluid to an outlet of the body and a valve seat on the body at the outlet. In each case, the valve includes a substantially rigid seal cap, an O-ring positioned between the seal cap and the valve body for maintaining a seal, and a spring washer. The spring washer centrally receives the head of a thermally responsive frangible element, in particular a glass bulb. The glass bulb is substantially rigid and is loaded in compression against the flexible washer by means of an adjustment screw substantially rigidly supported by a pair of yoke arms extending from the sprinkler body. The spring washer reduces the compressive preload required to protect the frangible element during normal operation. As a result, lighter and thinner walled frangible elements may be employed so as to provide a quicker response or triggering action at the selected threshold temperature, all without compromising the frangible element or the valve seat.